python - How to display Image in pygame?

Question

I want to load an image from webcam to display on pygame I am using videocapture

from VideoCapture import Device
import pygame
import time
In=1
pygame.init()
w = 640
h = 480
size=(w,h)
screen = pygame.display.set_mode(size) 

while True:
    cam = Device()
    cam.saveSnapshot(str(In)+".jpg") 
    img=pygame.image.load(In)
    screen.blit(img,(0,0))
    In=int(In)+1
    In=str(In)

Why does this not work.Pygame window opens but nothing displays?

Answer 1

You have to tell pygame to update the display.

Add the following line in your loop after blitting the image to the screen:

pygame.display.flip()

---

BTW, you probably want to limit how much images you take per second. Either use time.sleep or a pygame clock.

---

from VideoCapture import Device
import pygame
import time
In=1
pygame.init()
w = 640
h = 480
size=(w,h)
screen = pygame.display.set_mode(size) 
c = pygame.time.Clock() # create a clock object for timing

while True:
    cam = Device()
    filename = str(In)+".jpg" # ensure filename is correct
    cam.saveSnapshot(filename) 
    img=pygame.image.load(filename) 
    screen.blit(img,(0,0))
    pygame.display.flip() # update the display
    c.tick(3) # only three images per second
    In += 1